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The paper addresses issues in establishing a user-friendly systematic collection arrangement following a merger of two high school and college library collections classified according to UDC. In the way it was used, this scheme presented some weaknesses with respect to collection usage. Due to the disciplinary nature of UDC, subjects and phenomena are dispersed in the scheme according to the disciplines in which they are the subject of study. At the same time students in a school library often seek interdisciplinary subjects and need access to clusters of documents which according to UDC may be classed in several different knowledge areas. The author illustrates how this problem was resolved by re-arranging the collection according to phenomena. This was achieved by interpreting UDC numbers as if they represented specific phenomena. Thus, by superimposing some local indexing rules onto a disciplinary knowledge organization system it was possible to collocate interdisciplinary subjects under a single class number. Furthermore, by reversing subject numbers and form auxiliaries (atlases, dictionaries, textbooks etc.) which is an option envisaged in the design of UDC, documents were collocated in the way they are most frequently used by students. The author suggests that, in practice, one often needs to overcome the constraints of disciplinary classification and he discusses the approach used in his school library collection.

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The end-Ordovician mass extinction dramatically altered the course of conodont evolution. This extinction event is probably unique in that it can be strongly correlated with a glacial climatic control. This study has identified, through the application of high-resolution stratigraphy, events within the extinction and recovery intervals. Elements of the uppermost Ordovician Shelf-edge Biofacies were severely affected by the oceanic cooling and introduction of cold-water currents associated with the initiation of the glacial maximum. In contrast, elements of the Shelf Biofacies were more severely affected by the intense cooling, shallowing and overcrowding during the glacial maximum. A number of the Shelf-edge taxa that had survived the glacial maximum suffered extinction at the hands of increasing water temperatures, rising anoxia and/or the cessation of oceanic circulation during the post-glacial transgression. Recovery was initiated by the appearance of Crisis Progenitor Taxa within the glacial maximum in the Shelf Biofacies and during the post-glacial transgression in the Shelf- edge- Slope biofacies. The Shelf-edge Biofacies identified within the uppermost Ordovician is not recognised in the Lower Silurian. Two main biofacies occurred on the Shelf and Slope, which had directly evolved from their Upper Ordovician equivalents. The long-term recovery involved the evolution of Crisis Progenitor Taxa and Ecological Generalists within the Shelf and Slope Biofacies (autochthonous taxa). Punctuated equilibrium likely predominated in the Shelf Biofacies as a consequence of widely fluctuating physical conditions. In contrast, the more stable environments of the slope encouraged gradualistic evolution within the Slope Biofacies (Plus ça change Model). Transgressive episodes within the Llandovery, possibly linked to eccentricity cycles, caused the iterative appearance of Long-term Refugia Taxa (allochthonous taxa), sourced from a Pterospathodontid Biofacies. The transgressive episodes also drove elements of the Slope Biofacies onto the shelf. It has been observed that the mechanisms driving extinction, namely environmental disruption and temperature changes, were also responsible for fuelling the subsequent recovery.

A região costeira do Estado de São Paulo, entre Peruíbe (24o24\'30\'\'S, 46o54\'00\'\'W) e São Sebastião (23o50\'30\'\'S, 45o40\'00\'\'W) faz parte da Plataforma Continental Sudeste do Brasil (PCSE). A região possui grande importância econômica e social devido ao turismo, indústria de óleo e gás, e ao porto de Santos, o maior do país. Correntes sobre a plataforma continental interna (PCI) dessa região foram pouco estudadas antes do projeto ECOSAN. Durante o ECOSAN, dados de correntes foram obtidos por aproximadamente 10 meses (2005-2006), através de 4 fundeios: 3 localizados na PCI, próximo à isóbata de 20 m: em frente à Peruíbe (P20) (24o24\'30\'\'S, 46o54\'00\'\'W), em frente à Santos (S20) (24o03\'30\'\'S, 46o17\'30\'\'W), e próximo à ilha Montão de Trigo (M20) (23o50\'\'30\'S, 45o40\'\'00\'W); e 1 localizado na plataforma continental média (PCM), próximo à isóbata de 100 m, em frente à Santos (S100) (25o05\'00\'\'S, 45o42\'00\'\'W). Medições de ventos foram feitas durante o mesmo período através de 2 bóias meteorológicas, localizadas junto à P20 e M20, e na Lage de Santos (L30) (24o19\'48\'\'S, 46o11\'20,4\'\'W). Os dados foram analisados no domínio do tempo e da freqüência para estudar as características das correntes bem como a importância relativa das forçantes da circulação, principalmente: tensão de cisalhamento do vento, gradientes de pressão baroclínicos e troca de momentum entre a Corrente do Brasil (CB) e as águas mais internas da plataforma continental. Resultados mostraram que as componentes de corrente paralelas à topografia foram as mais energéticas, sendo aparentemente geostróficas. Correntes forçadas pelo vento na PCI foram observadas em P20 durante o verão e em M20. Já em S20, o vento não foi capaz de suplantar os efeitos baroclínicos causados pela descarga fluvial do sistema estuarino de Santos. Em períodos de ventos fracos M20 é forçada por efeitos baroclínicos, aparentemente sofrendo também influência do sistema estuarino de Santos. Em P20 durante o inverno foi constatada a presença de forçantes baroclínicas, sendo estas atribuídas às águas provenientes do sul, com influência do Rio da Prata, as quais possivelmente influenciam também a dinâmica da PCM. Durante o período amostrado não foi verificado nenhuma inuência direta da Corrente do Brasil sobre a PCM, e tampouco sobre a PCI, demonstrando que essas regiões possuem dinâmica distinta da plataforma continental externa. A circulação na plataforma continental estudada não é homogênea, apresentando um sistema complexo de uxos e contra-uxos, havendo uma tendência das correntes sobre a PCM e a PCI apresentarem sentidos opostos. Há também tendência das correntes na PCI apresentarem sentido predominante para NE sobretudo entre Santos e São Sebastião, enquanto que na PCM a direção predominante é para SW. / The São Paulo State coastal region located between the cities of Peruíbe (242430S, 465400W) and São Sebastião (235030S, 454000W) is part of the SouthBrazil Bight. This region has great economic and social importance due to the tourism, oil and gas industries and the presence of the largest Brazilian port (Santos). Currents at the regions inner-shelf were poorly sampled before the eld work of the ECOSAN project. During ECOSAN, current meter data was obtained for nearly 10 months (2005-2006), from 4 moorings: 3 deployed in the inner-shelf, near the 20 m isobath: in front of Peruíbe (P20) (242430S, 465400W), in front of Santos (S20) (240330S, 461730W) and near Montão de Trigo Island (M20) (235030S, 454000W); and 1 deployed at the mid-shelf, near the 100 m isobath, in front of Santos (S100) (25 0500S, 45 4200W). Wind time series were measured at the same period, at the two inner shelf moorings, P20 and M20, by a surface met-buoy, and at the Lage de Santos (L30) (241948S, 46 1120,4W). Current and wind data were analyzed in time and frequency domains for describing currents characteristics and comparing the relative importance of the forcing mechanisms for the inner-shelf circulation, mainly: wind-stress, baroclinic pressure gradients and Brazil Current momentum exchanges. Results showed that alongshelf current components were the most energetic and nearly geostrophic. Wind driven currents on the inner-shelf were observed on P20 during summer time and on M20, however on S20 the wind wasnt capable of overcoming baroclinic eects caused by river discharge from the Santos estuarine system. Over weak wind periods M20 was forced by baroclinic eects, apparently also inuenced by Santos estuarine system. Baroclinic forcing was observed on P20 during winter time, being atributed to waters from the south, under the inuence of the Plata River, possibly inuencing the mid-shelf as well. During the whole period there was no presence of Brazil Current eddies or meanders, showing that neither inner-shelf nor mid-shelf are inuenced by the outer-shelf dynamics. The continental shelf circulation is not homogeneous, with a complex pattern of uxes and counter-uxes, where currents have tendency to ow on opposite directions between mid and inner-shelf. There is also a tendency for currents on the inner-shelf to ow towards NE, speccialy between Santos and São Sebastião, and towards SW on the mid-shelf.

Shelf seas occupy only 7% in area and less than 0.5% in volume of the entire ocean, but they play an important role in the carbon cycle by taking about 20% - 50% of all the CO2 absorbed by the ocean. Diapycnal mixing is a key process in transporting nutrients, carbon, water mass etc. between the surface and the lower mixed layers in a seasonally stratified shelf sea. The identification and quantification of the processes responsible for driving diapycnal mixing in seasonally stratified seas are the subjects worth study. Early researchers have examined the correlation between enhanced bulk shear and the wind. The bulk shear is defined as the average of the shear in two defined layers which are either side of the thermocline. However the contribution from the barotropic tide has generally been neglected. This study examines two stages of the evolution of water column stratification: the spring development stage and the autumn break down stage. Rotary spectral analysis shows that the shear across thermocline corresponds to different drivers when the water stratification is different. At the spring development stage, the shear across the thermocline corresponds to near-inertial oscillations, which are related to wind. Whilst at the autumn break down stage, the shear across thermocline relates to both the near-inertial oscillations and the barotropic tide. Thus, in contraction to earlier research, our research suggests that the barotropic tide is another dominant driver in the generation of shear. However not all observations can be explained by the wind or barotropic tide. The additional consideration of the baroclinic tide helps explain the signal of an odd shear spike observed in the northern North Sea, which occurred during a period of weak shear production by the wind and barotropic tide. A 1D two-layer vertical dynamic numerical model and a 1D turbulence closure numerical model were applied to investigate the impact of wind and barotropic tide on shear, respectively. In addition, the impacts of hydrographic conditions on the driver of shear were considered. Coherence analysis was applied to examine the similarity of constituents (in frequency domain) between the modelled shear production and the observations. The model sensitivity analysis demonstrates that the switch of driver of shear is highly related to the depth ratio, which is the ratio of thermocline depth over water depth.